Thyroid Function in Term Infants With Respiratory Distress

Thyroid Function in Term and Near Term Infants With Respiratory Distress and Its' Relation to Severity of Illness

This study was designed to evaluate the level of certain hormones (thyroid hormones and cortisol) in full term or close to full term infants who have respiratory distress severe enough to require respiratory support. The purpose of this study is to determine if there is a relationship between these hormone levels and how sick these infants are who require help with breathing following birth.

Hypothesis: Infants who are born full term or near full term and who have low hormone levels will have higher severity of illness.

Study Overview

• Status: Completed
• Conditions: Infant, Newborn; Transient Hypothyroxinemia

Detailed Description

Transient hypothyroxinemia, as demonstrated by low T4 and free T4 levels with normal levels of TSH, in preterm infants has been associated with increased severity of illness and adverse outcomes. Effects of thyroid function in term infants is less well studied. Previous research in the Special Care Nursery at Christiana Hospital has indicated that transient hypothyroxinemia in intubated term infants was associated with increased severity of illness and the need for more intensive rescue therapies. However, free T4, the biologically active substance was not measured in our previous study.

Infants who meet criteria for the study will begin participation after parental informed consent is obtained. Infants who are enrolled will have serial measurements of thyroid stimulating hormone (TSH), T4, free T4, free T3, and cortisol. These measurements will be obtained at four specific time intervals throughout the first week of the infant's life. The medical team will be blinded to the results of the hormone testing. The results will be reviewed by an unblinded study investigator and an endocrinologist will be consulted if abnormal results are reported.

These hormone levels will be compared with severity of illness and level of respiratory support needed in order to establish an association between thyroid function and illness severity. Illness severity will be quantified by using the Score for Neonatal Acute Physiology (SNAP). SNAP scores require collecting data from vital signs and results of labs that are considered standard of care.

• Study Type: Observational
• Enrollment (Actual): 20

Contacts and Locations

Study Locations

• United States
  • Delaware
    • Newark, Delaware, United States, 19718
      • Christiana Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: No older than 6 days (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Full-term and near-term infants with respiratory distress during the first 24 hours of life.

Description

Inclusion Criteria:

• Infants born > or = to 35 weeks gestation
• Infants admitted to the neonatal intensive care unit at Christiana Hospital
• Respiratory distress requiring use of mechanical ventilation or nasal CPAP (continuous positive airway pressure)
• Parental informed consent

Exclusion Criteria:

• Infants born < 35 weeks gestation
• Infants with documented congenital abnormalities which directly impact the cardiorespiratory system

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
1; Full-term and near-term infants with respiratory distress in the first 24 hours of life

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
To determine if thyroid function, particularly free T4, is associated with severity of illness in term and near term infants with respiratory distress who require endotracheal intubation or nasal CPAP.	Birth until 120 hours of life

Collaborators and Investigators

• Sponsor: Christiana Care Health Services
• Investigators: Principal Investigator: David A. Paul, MD, Christiana Care Health Systems; Principal Investigator: Erika M. Yencha, MD, Christiana Care Health Systems

Publications and helpful links

General Publications

• Huang CB, Chen FS, Chung MY. Transient hypothyroxinemia of prematurity is associated with abnormal cranial ultrasound and illness severity. Am J Perinatol. 2002 Apr;19(3):139-47. doi: 10.1055/s-2002-25308.
• Paul DA, Leef KH, Voss B, Stefano JL, Bartoshesky L. Thyroxine and illness severity in very low-birth-weight infants. Thyroid. 2001 Sep;11(9):871-5. doi: 10.1089/105072501316973136.
• Lim DJ, Herring MK, Leef KH, Getchell J, Bartoshesky LE, Paul DA. Hypothyroxinemia in mechanically ventilated term infants is associated with increased use of rescue therapies. Pediatrics. 2005 Feb;115(2):406-10. doi: 10.1542/peds.2004-0192.
• Watterberg KL, Gerdes JS, Cook KL. Impaired glucocorticoid synthesis in premature infants developing chronic lung disease. Pediatr Res. 2001 Aug;50(2):190-5. doi: 10.1203/00006450-200108000-00005.
• Simpson J, Williams FL, Delahunty C, van Toor H, Wu SY, Ogston SA, Visser TJ, Hume R; Scottish Preterm Thyroid Group. Serum thyroid hormones in preterm infants and relationships to indices of severity of intercurrent illness. J Clin Endocrinol Metab. 2005 Mar;90(3):1271-9. doi: 10.1210/jc.2004-2091. Epub 2004 Dec 21.
• Richardson DK, Gray JE, McCormick MC, Workman K, Goldmann DA. Score for Neonatal Acute Physiology: a physiologic severity index for neonatal intensive care. Pediatrics. 1993 Mar;91(3):617-23.

Study record dates

Study Major Dates

• Study Start: January 1, 2006
• Primary Completion (Actual): July 1, 2006
• Study Completion (Actual): July 1, 2006

Study Registration Dates

• First Submitted: February 16, 2006
• First Submitted That Met QC Criteria: February 16, 2006
• First Posted (Estimate): February 20, 2006

Study Record Updates

• Last Update Posted (Estimate): January 18, 2008
• Last Update Submitted That Met QC Criteria: January 16, 2008
• Last Verified: January 1, 2008

More Information

Terms related to this study

• Keywords: respiratory distress; thyroid disease; near term infants; hypothyroxinemia; full term infants
• Additional Relevant MeSH Terms: Endocrine System Diseases; Thyroid Diseases
• Other Study ID Numbers: 25190